Dave wrote:
There may well be complete, transportable charting software somewhere, I just haven't been able to find it.
Hi Dave, have you checked out Highcharts at all?
http://www.highcharts.com/
They have two forms of charting software, one being highcharts and the other is highstocks, take your pick.
You don't need to reference or access their servers to be able to produce trends, they make their code available as a library, so you can host it yourself.
The chart you have on your blog site Dave looks to be the same as what highstocks looks like.
They have extra modules which allow you to export and to print the chart.
I'd say that was pretty transportable.
Regards,
Paul